They say new laws may be necessary amid rising cyber attacks that threaten the privacy of personal data.

"This dais has an obligation to make a law and not just wag our fingers," said Senator Brian Schatz, a Democrat from Hawaii, at the meeting of the Senate Commerce, Science and Transportation Committee.

The hearing comes after Equifax said failure to install a security update may have led to exposure of information of more than 145 million people in the US and almost 700,000 people in the UK.

Verizon, which now owns Yahoo, last month also said two breaches in 2013 and 2014 exposed 3 billion customer accounts - far more than the initial estimate.